What is the weight limit with suit cases on airplanes?

im flying with alaska airlines and i need to know if they have a weight limit on suit cases?

Check with the airline's customer service department. It is usually 50 lbs per bag, with a two bag limit.

Usually 50 pounds.

It depends on the airline. For alaska airlines here are the limits according to their website:

You're allowed one carry-on bag, which can measure up to 10" H x 17" W x 24" L (25 x 43 x 61 cm), plus one personal item, such as a purse, briefcase or laptop computer. At least one of the items should be stowed under the seat in front of you.

You're allowed up to two pieces of checked baggage. Each bag can be a maximum of 62 linear inches (length + width + height) and may weigh up to 50 pounds. Excess baggage charges apply to additional pieces, overweight pieces between 51 and 100 pounds and oversized pieces of luggage.

No single piece of checked baggage may weigh more than 100 pounds. Any piece in excess of 100 pounds must be forwarded via air cargo or alternative means arranged by the customer.

The following exceptions to the baggage allowance rules apply:

* Customers traveling intra-Alaska or to/from GDL or MEX shall be permitted to check three pieces of baggage up to 62 inches, 50 pounds each.
* When the third bag is fishing equipment (two rods, two reels, and one tackle box), the third bag shall be free.
* Military personnel on active duty are allowed two duffle bags up to 70 lbs. per bag and up to 115 inches free allowance.
* Customers making international connections to other airlines shall follow the weight restrictions of the international carrier, which may permit them to have bags heavier than Alaska Airlines' free allowance.
* Disabled customers' assistive devices, strollers and car seats do not count for checked baggage allowance.